1. Field of the Invention
The present invention relates to actuators, and, more particularly, to actuators with flexible members.
2. Description of the Related Art
Pneumatic actuators utilize pressurized gas, such as air, to push against workpieces. Pneumatic actuators are known that include a stiff base member and a flexible member connected to the base member, with an air chamber between the flexible member and stiff base member. When the air chamber fills with pressurized air, the pressure from the air forces the flexible member away from the stiff base member and allows the surface of the flexible member to produce work on a workpiece.
To prevent destruction of the pneumatic actuator, the flexible member should not be allowed to excessively expand in the radial direction due to pressurization, or else it could rupture. The sidewall stiffness of the flexible member can affect the flexible member's resistance to rupturing and is related to the flexible member's geometry, material properties, or a combination thereof. While a high sidewall stiffness of the flexible member better resists rupture, the high sidewall stiffness can cause the flexible member to have problems returning to a collapsed position when pressurization is removed. Similarly, if the sidewall stiffness is too high, high stresses can be developed in the flexible member which lead to durability issues.
What is needed in the art is an actuator with a flexible member that can overcome some of the previously described disadvantages.